DynaRing: A Patient-Specific Mitral Annuloplasty Ring With Selective Stiffness Segments.

Area of Science:

• Biomaterials Science
• Cardiovascular Engineering
• Medical Device Design

Background:

• Annuloplasty ring selection and design are crucial for successful mitral valve (MV) repair.
• Current annuloplasty rings may lack the adaptability for patient-specific needs.
• DynaRing aims to address these limitations with a selectively compliant design.

Purpose of the Study:

• To evaluate the performance and design adaptability of the DynaRing annuloplasty device.
• To assess the DynaRing's ability to provide physiological annular dynamics and enable patient-specific tuning.
• To validate a patient-specific design approach using finite element modeling and MRI data.

Main Methods:

• The DynaRing was evaluated in explanted porcine valves using an ex-vivo left heart simulator.
• A 150 million cycle fatigue test was conducted using a custom oscillatory system.
• A finite element model optimization, integrated with patient MRI data, was used for patient-specific design.

Main Results:

• Ex-vivo experiments showed DynaRing motion comparable to healthy native annuli.
• The DynaRing demonstrated durability through extensive fatigue testing.
• Patient-specific optimization successfully tuned ring parameters, adjusting key MV metrics up to 19.8%.

Conclusions:

• The DynaRing is a selectively compliant annuloplasty device that supports the mitral annulus while allowing physiological dynamics.
• A patient-specific design approach effectively utilizes DynaRing's tunable properties to match individual patient anatomy.
• DynaRing shows promise for improving long-term efficacy in mitral valve repair through personalized device adaptation.